of belleville



B. P. GEIST. METHOD OF MAKING DIES. APPLICATION FILED JAN 30. I919 Patented Dec. 16,1919.-

Q I I WITAESS IJVVEJV'TOR.

, B. P Gent.

ATTORNEY.

UNITED STATES PATENT OFFICE.

- BURNETT P. GEIQST, or BELLEVILLE, ILLINOIS, ASSIGNOB TO IDEAL STENCIL MACHINE COMPANY, or BELLEVILLE, ILLINoIs, A CORPORATION or ILLINOIS.

METHCI) or MAKING DIES.

Specification of Letters Patent. t t 1 191 Applicationfiled January 35, 1919. Serial No. 274,069.

To all whom it may concern:

Be it known that I, BURNETT P. GEIs'r, a

St. Clair, State of Illinois, United States of' America, have invented a certain new and useful Method of Making Dies, of which the following is such a full, clear, and exact description as will enable any one skilled 1n the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

My invention relates to a method of forming dies and more particularly such dies as are used in stencil machines to cut paper, thin metal, or the like.

Heretofore such dies have usually been formed by punching a character out of a blank of sheet steel after which the necessary clearance is provided by hand filing the die from the rear to the front. This not only requires considerable skilled labor, but is also likely to produce dies with broken on roughened edges inasmuch as 1t 1s obvlous that the opening in the face of the die cannot be enlarged as it must fit a punch of predetermined size.

The object of my invention is to provide a method of forming a die whereby the hand filing of the die is entirely eliminated and at the same time the production of broken or uneven cutting edges is obviated.

In the accompanying drawings which illustrate a die made in accordance with my invention together with the necessary punches for producing the same, Flgure 1 is a view of the die after the first operation. Fig. 2 is a similar view after the second operation, Fig. 3 is a smiliar v ew after the third operation, Fig. 4: is a vlew taken on the line 4-4t of Fig. 1, showing the master punch and die in osition, Fig. 5 is a section taken on the line 55 of Fig. 2 showing the second punch and solid die block in position, and Fig. 6 is a section taken on the line 66 of Fig. 3 showing the completed die.

In forming the die, I use a blank 10 of sheet steel which is provided with suitable means for centering it under the punch, such for instance, as the circular openings 11 which may also serve to hold the completed die in p tion pon its support. The blank 10 is placed in position upon a suitable master die 12 andthe character 13 is punched out by means of a master punch 14:. so as to leave the blank in the form shown in Fig. 1' i of the drawings. This is the usual first operation in forming a stencil machine dle. After this operation has been performed instead of hand filing the opening 13 to produce the necessary clearance the blank 10 is placed face down on a solid die block 15 and a second punch 16 similar in contour to the master punch 14 but slightly larger in all dimensions is forced from the rear face partially through the blank 10, preferably about two thirds of the way, as shown in Fig. 5. This operation shaves the edges of the opening 10 and causes the surplus metal to be compressed and expanded to form edges 17, as shown in Figs. 2 and '5, which extend beyond the original terminations of the opening 13. This compression and expansion of the metal fills in any broken or irregular parts which might occur in the original face edges of the die opening. The blank 10 is now placed upon the original master die 12 and the original master punch 14: is again forced through the die from the rear to trim off the surplus portions of the edges 17 as best shown in Fig. 3. In order to complete the die, it is only necessary to harden the blank 10 and to level oif the face 18 of the die, preferably by grinding, so as to produce sharp cutting edges 19*.

It will be evident that by the use of my process a die with the necessary clearance and without broken or uneven cutting edges is produced without the expense of any hand filing.

Having fully described my invention, what I claim and desire to secure by Letters Patent of the United States is:

1. The method of forming a die which comprises punching a character through a blank of metal by. means of a master punch, forcing a second punch of larger size but similar contour to the master punch partially through the blank from the rear face thereof to expand the metal adjacent to the forcing a second punch of larger size but similar contour to the master punch partially through the blank from the rear face thereof to expand the metal adjacent to the edges of the character laterally to reduce the opening in the blank, trimming the expanded edges, hardening the blank, and leveling the face of the blank to produce cutting edges.

3. The method of forming a die which comprises punching a chcracter through a t blank of metal by means of a master punch,

' forcing a second punch of larger size but similar contour to the master punch partially through the blank from the rear face thereof to expand the metal adjacent to the edges of the character, and trimming the exsimilar contour to the master punch partially through the blank from the rear face thereof to expand the metal adjacent to the edges of the character, trimming the expanding edges by means of the original master punch, hardening the blank, and leveling the face of the blank to produce cutting edges.

In testimony whereof, I have hereunto set my hand and affixed my seal.

BURNETT P. GEIST. [1,. s.] 

